System crashes and blue screen of death may be caused at least in part by malware infestations on affected machines. Each machine had been previously infected with a rootkit, a set of tools sometimes installed by malware that are designed to hide the presence of the infection on the host system. Restoring from a known-good backup would be ideal, however most home users sadly do not have backup images to rely upon. Microsofts Security Essentials anti-virus tool detects the invader as Win32/Alureon.”]
Source: https://krebsonsecurity.com/2010/02/rootkit-may-be-culprit-in-recent-windows-crashes/